diff --git a/package-lock.json b/package-lock.json
index 8666c94..1769440 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -17,7 +17,7 @@
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           "resolved": "https://registry.npmjs.org/minimalistic-assert/-/minimalistic-assert-1.0.1.tgz",
@@ -17875,6 +18148,11 @@
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         },
+        "module-error": {
+          "version": "1.0.2",
+          "resolved": "https://registry.npmjs.org/module-error/-/module-error-1.0.2.tgz",
+          "integrity": "sha512-0yuvsqSCv8LbaOKhnsQ/T5JhyFlCYLPXK3U2sgV10zoKQwzs/MyfuQUOZQ1V/6OCOJsK/TRgNVrPuPDqtdMFtA=="
+        },
         "napi-macros": {
           "version": "2.0.0",
           "resolved": "https://registry.npmjs.org/napi-macros/-/napi-macros-2.0.0.tgz",
@@ -17956,6 +18234,11 @@
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           "integrity": "sha1-RQ1Nyfpw3nMnYvvS1KKJgUGaDM8=",
           "bundled": true
+        },
+        "ws": {
+          "version": "8.2.3",
+          "resolved": "https://registry.npmjs.org/ws/-/ws-8.2.3.tgz",
+          "integrity": "sha512-wBuoj1BDpC6ZQ1B7DWQBYVLphPWkm8i9Y0/3YdHjHKHiohOJ1ws+3OccDWtH+PoC9DZD5WOTrJvNbWvjS6JWaA=="
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@@ -19044,7 +19327,8 @@
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+      "optional": true
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@@ -19356,6 +19640,7 @@
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+      "optional": true,
       "requires": {
         "catering": "^2.1.0"
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@@ -19458,7 +19743,8 @@
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-      "integrity": "sha512-E486g1NCjW5cF78KGPrMDRBYzPuueMZ6VBXHT6gC7A8UYWGiM14fGgp+s/L1oFfDWSPV/+SFkYCmZ0SiESkRKA=="
+      "integrity": "sha512-E486g1NCjW5cF78KGPrMDRBYzPuueMZ6VBXHT6gC7A8UYWGiM14fGgp+s/L1oFfDWSPV/+SFkYCmZ0SiESkRKA==",
+      "optional": true
     },
     "level-write-stream": {
       "version": "1.0.0",
@@ -20113,9 +20399,9 @@
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     },
     "nunjucks": {
-      "version": "3.2.3",
-      "resolved": "https://registry.npmjs.org/nunjucks/-/nunjucks-3.2.3.tgz",
-      "integrity": "sha512-psb6xjLj47+fE76JdZwskvwG4MYsQKXUtMsPh6U0YMvmyjRtKRFcxnlXGWglNybtNTNVmGdp94K62/+NjF5FDQ==",
+      "version": "3.2.4",
+      "resolved": "https://registry.npmjs.org/nunjucks/-/nunjucks-3.2.4.tgz",
+      "integrity": "sha512-26XRV6BhkgK0VOxfbU5cQI+ICFUtMLixv1noZn1tGU38kQH5A5nmmbk/O45xdyBhD1esk47nKrY0mvQpZIhRjQ==",
       "requires": {
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@@ -20191,9 +20477,9 @@
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     "openzeppelin-solidity": {
-      "version": "2.2.0",
-      "resolved": "https://registry.npmjs.org/openzeppelin-solidity/-/openzeppelin-solidity-2.2.0.tgz",
-      "integrity": "sha512-HfQq0xyT+EPs/lTWEd5Odu4T7CYdYe+qwf54EH28FQZthp4Bs6IWvOlOumTdS2dvpwZoTXURAopHn2LN1pwAGQ=="
+      "version": "4.8.1",
+      "resolved": "https://registry.npmjs.org/openzeppelin-solidity/-/openzeppelin-solidity-4.8.1.tgz",
+      "integrity": "sha512-KM0pVpfrCBdifqN2ZeJZFvFuoGz3GmI4Ty/ceKNkcaf7VVWo/rLOfc5EiLh+Ukb5NadNmYo8WMeGhFA8hVWDpg=="
     },
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@@ -20782,7 +21068,8 @@
     "queue-microtask": {
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       "resolved": "https://registry.npmjs.org/queue-microtask/-/queue-microtask-1.2.3.tgz",
-      "integrity": "sha512-NuaNSa6flKT5JaSYQzJok04JzTL1CA6aGhv5rfLW3PgqA+M2ChpZQnAC8h8i4ZFkBS8X5RqkDBHA7r4hej3K9A=="
+      "integrity": "sha512-NuaNSa6flKT5JaSYQzJok04JzTL1CA6aGhv5rfLW3PgqA+M2ChpZQnAC8h8i4ZFkBS8X5RqkDBHA7r4hej3K9A==",
+      "optional": true
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diff --git a/package.json b/package.json
index a4f9825..4d7cb87 100644
--- a/package.json
+++ b/package.json
@@ -27,7 +27,7 @@
     "ganache": "^7.5.0",
     "ganache-cli": "^6.12.2",
     "nunjucks": "^3.2.0",
-    "openzeppelin-solidity": "2.2.0",
+    "openzeppelin-solidity": "4.8.1",
     "solidity-rlp": "^2.0.0",
     "truffle": "^5.10.1",
     "web3": "4.11.0"